Sleep-disordered breathing and nocturnal hypoxemia in chronic thromboembolic pulmonary disease

BACKGROUND AND AIMS

Sleep-disordered breathing (SDB) and nocturnal hypoxemia were known to be present in patients with chronic thromboembolic pulmonary hypertension (CTEPH), but the difference between SDB and nocturnal hypoxemia in patients who have chronic thromboembolic pulmonary disease (CTEPD) with or without pulmonary hypertension (PH) at rest remains unknown.

METHODS

Patients who had CTEPH (n = 80) or CTEPD without PH (n = 40) and who had undergone sleep studies from July 2020 to October 2022 at Shanghai Pulmonary Hospital were enrolled. Nocturnal mean SpO2 (Mean SpO2) <90% was defined as nocturnal hypoxemia, and the percentage of time with a saturation below 90% (T90%) exceeding 10% was used to evaluate the severity of nocturnal hypoxemia. Logistic and linear regression analyses were performed to investigate the difference and potential predictor of SDB or nocturnal hypoxemia between CTEPH and CTEPD without PH.

RESULTS

SDB was similarly prevalent in CTEPH and CTEPD without PH (P = 0.104), both characterised by obstructive sleep apnoea (OSA). Twenty-two patients with CTEPH were diagnosed with nocturnal hypoxemia, whereas only three were diagnosed with CTEPD without PH (P = 0.021). T90% was positively associated with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance in patients with CTEPH and CTEPD without PH (P < 0.001); T90% was also negatively related to cardiac output in these patients. Single-breath carbon monoxide diffusing capacity, sex and mPAP were all correlated with nocturnal hypoxemia in CTEPH and CTEPD without PH (all P < 0.05).

CONCLUSION

Nocturnal hypoxemia was worse in CTEPD with PH; T90%, but not SDB, was independently correlated with the hemodynamics in CTEPD with or without PH.

Correlations between objective and subjective outcomes after adenotonsillar surgery in children with OSA

Objectives

To investigate whether the OSA-18 questionnaire and a postoperative patient-reported outcome measure (PROM) question correlated with polysomnography (PSG) data.

Methods

A prospective study of otherwise healthy young children with moderate to severe obstructive sleep apnea (OSA) to investigate if the obstructive apnea-hypopnea index (OAHI) before and 6-12 months after adenotonsil surgery correlated with the OSA-18 total symptom score (TSS) and the sleep disturbance subscale (SDS), as well as a PROM question on symptom improvement with responses on a 4-grade Likert scale.

Results

Of 201 children, 173 (86%) had complete data of OAHI and OSA-18 pre- and postoperatively. The mean age was 3.2 years (SD 1.0) and the mean OAHI was 15.9 (11.3). Significant correlations between changes in the OAHI and OSA-18 were found, both TSS (r = 0.29, p < .001) and SDS (r = 0.53, p < .001). A total of 136 (68%) patients responded to the PROM question, the majority of whose symptoms had disappeared (n = 102) or almost disappeared (n = 30). Four patients had unchanged symptoms, and none had worsening symptoms. A correlation was found between the PROM question and a change in the OAHI (r = 0.36, p < .001), as well as a change in the OSA-18 TSS (r = 0.24, p = .006) and the SDS (r = 0.34, p < .001). The specificity of the PROM question for prediction of a postoperative OAHI < 2 was 82%, and the sensitivity was 38%.

Conclusion

Changes in the OAHI significantly correlated with changes in the OSA-18, especially with the sleep disturbance scale, which could be an alternative for evaluation at follow-ups.

Level of Evidence

3.

Ten-Year Trends in Sleep-Disordered Breathing After Ischemic Stroke: 2010 to 2019 Data From the BASIC Project

Background Despite good evidence that the prevalence of sleep-disordered breathing (SDB) is increasing in the general population, no data are available about trends in poststroke SDB. We therefore sought to assess changes in poststroke SDB over a 10-year period (2010-2019). Methods and Results Participants in the BASIC (Brain Attack Surveillance in Corpus Christi) project were offered a home sleep apnea test to assess for SDB after stroke. SDB assessment procedures remained unchanged throughout the study period. Respiratory event index was calculated as the sum of apneas and hypopneas per hour of recording. SDB was defined as respiratory event index ≥10/h for optimal sensitivity and specificity of the home sleep apnea test device compared with in-laboratory polysomnography. Regression models were used to test associations between SDB prevalence and severity and time, with adjustment for multiple potential confounders. Among the 1215 participants who completed objective sleep apnea testing, the prevalence of SDB grew from 61% in the first year of the study to 76% in the last, with 1.1 times higher odds each year (95% CI, 1.07-1.19), after adjustment. A linear association was identified between time and respiratory event index (average annual respiratory event index increase of 0.56/h; 95% CI, 0.20/h-0.91/h), after adjustment. There was no difference in time trends by sex or ethnicity. Conclusions The prevalence and severity of SDB after ischemic stroke has increased over the past 10 years in this population-based cohort. These data highlight the need to determine whether SDB treatment improves stroke outcomes.

Sleep-Disordered Breathing and Cardiovascular Disease in Children and Adolescents: A Scientific Statement From the American Heart Association

Obstructive sleep apnea (OSA) is a known risk factor for cardiovascular disease in adults. It is associated with incident systemic hypertension, arrhythmia, stroke, coronary artery disease, and heart failure. OSA is common in children and adolescents, but there has been less focus on OSA as a primary risk factor for cardiovascular disease in children and adolescents. This scientific statement summarizes what is known regarding the impact of sleep‐disordered breathing and, in particular, OSA on the cardiovascular health of children and adolescents. This statement highlights what is known regarding the impact of OSA on the risk for hypertension, arrhythmia, abnormal ventricular morphology, impaired ventricular contractility, and elevated right heart pressure among children and adolescents. This scientific statement also summarizes current best practices for the diagnosis and evaluation of cardiovascular disease–related complications of OSA in children and adolescents with sleep apnea and highlights potential future research in the area of sleep‐disordered breathing and cardiovascular health during childhood and adolescence.

A review of therapies for the overlap syndrome of obstructive sleep apnea and chronic obstructive pulmonary disease

Obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) are common chronic diseases. These two noncommunicable diseases (NCDs) are prevalent among approximately 10% of the general population. Approximately 1% of the population is affected by the co-existence of both conditions, known as the overlap syndrome (OS). OS patients suffer from greater degrees of nocturnal oxygen desaturation and cardiovascular consequences than those with either condition in isolation. Besides OS, patients with COPD may suffer from a spectrum of sleep-related breathing disorders, including hypoventilation and central sleep apnea. The article provides an overview of the pathogenesis, associated risk factors, prevalence, and management of sleep-related breathing disorders in COPD. It examines respiratory changes during sleep caused by COPD and OSA. It elaborates upon the factors that link the two conditions together to lead to OS. It also discusses the clinical evaluation and diagnosis of these patients. Subsequently, it reviews the pathophysiological basis and the current evidence for three potential therapies: positive airway pressure therapy [including continuous positive airway pressure (CPAP) and bilevel positive airway pressure], oxygen therapy, and pharmacological therapy. It also proposes a phenotypic approach toward the diagnosis and treatment of OS and the entire spectrum of sleep-related breathing disorders in COPD. It concludes with the current evidence gaps and future areas of research in the management of OS.

Occurrence of Coronary Collaterals in Acute Myocardial Infarction and Sleep Apnea

Background In patients with acute myocardial infarction (MI), cardioprotective effects of obstructive sleep apnea are postulated on account of hypoxemic preconditioning. The aim of this single-center substudy was to investigate a potential association between obstructive sleep apnea and the presence of coronary collaterals in patients with first-time acute MI who have been enrolled in an ongoing, multicenter clinical trial. Methods and Results In TEAM-ASV I (Treatment of Sleep Apnea Early After Myocardial Infarction With Adaptive Servo-Ventilation Trial; NCT02093377) patients with first acute MI who received a coronary angiogram within 24 hours after onset of symptoms underwent polygraphy within the first 3 days. Coronary collaterals were classified visually by assigning a Cohen-Rentrop Score (CRS) ranging between 0 (no collaterals) and 3. Of 94 analyzed patients, 14% had significant coronary collaterals with a CRS ≥2. Apnea-Hypopnea Index (AHI) score was significantly higher in patients with CRS ≥2 compared with those with CRS <2 (31/hour [11-54] versus 13/hour [4-27]; P=0.032). A multivariable regression model revealed a significant association between obstructive AHI and CRS ≥2 that was independent of age, sex, body mass index, and culprit lesion left anterior descending artery (odds ratio [OR], 1.06; 95% CI, 1.01-1.12; P=0.023), but no significant association between coronary collaterals and central AHI (OR, 1.02; 95% CI, 0.97-1.08; P=0.443). Conclusions Patients with first-time acute MI had more extensive coronary collateralization with an increased AHI or rather an increased obstructive AHI. This finding supports the hypothesis that obstructive sleep apnea exerts potential cardioprotective effects, in addition to its known deleterious effects, in patients with acute MI. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02093377.

Intermittent Hypoxia Triggers Early Cardiac Remodeling and Contractile Dysfunction in the Time-Course of Ischemic Cardiomyopathy in Rats

BACKGROUND Sleep-disordered breathing is associated with a poor prognosis (mortality) in patients with ischemic cardiomyopathy. The understanding of mechanisms linking intermittent hypoxia (IH), the key feature of sleep-disordered breathing, to ischemic cardiomyopathy progression is crucial for identifying specific actionable therapeutic targets. The aims of the present study were (1) to evaluate the impact of IH on the time course evolution of cardiac remodeling and contractile dysfunction in a rat model of ischemic cardiomyopathy; and (2) to determine the impact of IH on sympathetic activity, hypoxia inducible factor-1 activation, and endoplasmic reticulum stress in the time course of ischemic cardiomyopathy progression. METHODS AND RESULTS Ischemic cardiomyopathy was induced by a permanent ligature of the left coronary artery in male Wistar rats (rats with myocardial infarction). Rats with myocardial infarction were then exposed to either IH or normoxia for up to 12 weeks. Cardiac remodeling and function were analyzed by Sirius red and wheat germ agglutinin staining, ultrasonography, and cardiac catheterization. Sympathetic activity was evaluated by spectral analysis of blood pressure variability. Hypoxia-inducible factor-1α activation and burden of endoplasmic reticulum stress were characterized by Western blots. Long-term IH exposure precipitated cardiac remodeling (hypertrophy and interstitial fibrosis) and contractile dysfunction during the time course evolution of ischemic cardiomyopathy in rodents. Among associated mechanisms, we identified the early occurrence and persistence of sympathetic activation, associated with sustained hypoxia-inducible factor-1α expression and a delayed pro-apoptotic endoplasmic reticulum stress. CONCLUSIONS Our data provide the demonstration of the deleterious impact of IH on post-myocardial infarction remodeling and contractile dysfunction. Further studies are needed to evaluate whether targeting sympathetic nervous system or HIF-1 overactivities could limit these effects and improve management of coexisting ischemic cardiomyopathy and sleep-disordered breathing.

A new office-based procedure for treatment of snoring: The S.I.Le.N.C.E. study

OBJECTIVE

Demonstrate the safety and effectiveness of palatal foreshortening and stiffening in reducing snoring severity in nonobstructive sleep apnea (non-OSA) patients complaining of chronic disruptive snoring.

METHODS

In a US-based 8-center, open-label, prospective, single-arm cohort study, 52 consenting adults with chronic disruptive snoring (snoring impacting a patient's life and causing patient or bed partner to seek medical intervention) were treated via office-based placement of resorbable, bidirectional, barbed suture implants into the soft palate under local anesthesia. Prior to intervention, home sleep tests (HSTs) were performed to rule out OSA and to document snoring noise level. Both subject and their bed/sleep partners (also consented) completed questionnaires including: bed/sleep partner's scored visual analog scale (VAS) for subjects' snoring severity, and subject scoring for Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI). Following intervention, HSTs, VAS, ESS and PSQI were repeated at 30, 90 and 180 days.

RESULTS

Mean baseline bed/sleep partner VAS was 7.81 ± 1.59. Mean postimplant VAS scores decreased significantly at each measured interval; to 5.77±2.35 (P < .001) at 30 days, 4.48 ± 1.81 (P < .001) at 90 days, and 5.40 ± 2.28 (P < .001) at 180 days. Post treatment improvements in daytime sleepiness and QOL were also observed. Two partial extrusions were reported. No further adverse events were identified.

CONCLUSION

The current study demonstrates the safety and efficacy of the Elevoplasty procedure in reducing snoring severity over a follow-up period of 6 months.

LEVEL OF EVIDENCE

2b.

Culprit Plaque Characteristics in Patients With Sleep-Disordered Breathing Undergoing Percutaneous Coronary Intervention: An Intravascular Ultrasound Study

Background

Sleep‐disordered breathing (SDB) is a novel cardiovascular risk factor. However, the coronary plaque characteristics of patients with SDB with coronary artery disease are still unclear.

Methods and Results

This study included 289 consecutive patients with coronary artery disease undergoing percutaneous coronary intervention. Plaque characteristics of the culprit lesion were assessed by preintervention intravascular ultrasound. The presence of SDB was defined as a 3% oxygen desaturation index of ≥15 events per hour measured by nocturnal pulse oximetry. Of 289 patients, the median 3% oxygen desaturation index was 9.6 (interquartile range, 5.1–16.6), and 88 patients (30.4%) were defined as having SDB. Compared with the no‐SDB group, the SDB group had a larger total atheroma volume of the culprit lesion (224.5 mm³ versus 190.8 mm³, P=0.05). The median maximum attenuation and calcification angle were 140° and 130°, respectively. Attenuated plaque with a maximum attenuation angle >140° was more frequently observed in the SDB group compared with the no‐SDB group (34.9% versus 22.6%; P=0.03). However, there were no statistically significant differences between groups in the maximum calcium angle and the frequency of calcific plaques with a maximum calcium angle >130°. Multivariable logistic regression analysis showed that the presence of SDB was a significant predictor of a greater ultrasound attenuation angle (>140°) (odds ratio, 1.86; 95% confidence interval, 1.02–3.39; P=0.04).

Conclusions

SDB was associated with larger atheroma plaque volume and a greater ultrasound attenuation, which are discriminators of plaque vulnerability. Further studies are needed to clarify the effects of SDB treatment on coronary plaque lesions.

Spinal cord injury is associated with enhanced peripheral chemoreflex sensitivity

Sleep‐disordered breathing (SDB) is prevalent in individuals with chronic spinal cord injury (SCI), but the exact mechanism is unknown. The aim of this study was to investigate whether peripheral chemoreceptors activity is enhanced in individuals with chronic SCI compared to abled‐bodied control subjects using CO₂ and O₂ chemical tests. In protocol (1) 30 subjects (8 cervical [cSCI], 7 thoracic [tSCI] and 15 able‐bodied [AB]) were studied to determine the ventilatory response to hyperoxia during wakefulness in the supine position. In protocol (2) 24 subjects (6 cSCI, 6 tSCI, and 12 AB subjects) were studied to determine the ventilatory response to a single breath of CO₂ (SBCO₂). The chemoreflex response to SBCO₂ was calculated as ∆V_E/∆CO₂ (L/min/mmHg). The ventilatory response to hyperoxia was defined as the % change in V_T following acute hyperoxia compared to preceding baseline. During hyperoxia SCI subjects had a significant decrease in V_T and V_E (63.4 ± 21.7% and 63.1 ± 23.0% baseline, respectively, P < 0.05) compared to AB (V_T: 87.1 ± 14.3% and V_E: 91.38 ± 15.1% baseline, respectively, P < 0.05). There was no significant difference between cSCI and tSCI in the V_T or V_E during hyperoxia (P = NS). There was no significant correlation between AHI and V_E% baseline (r = −0.28) in SCI and AB (n = 30). SCI participants had a greater ventilatory response to an SBCO₂ than AB (0.78 ± 0.42 L/min/mmHg vs. 0.26 ± 0.10 L/min/mmHg, respectively, P < 0.05). Peripheral ventilatory chemoresponsiveness is elevated in individuals with chronic SCI compared to able‐bodied individuals.

Impact of Sleep-Disordered Breathing on Long-Term Outcomes in Patients With Acute Coronary Syndrome Who Have Undergone Primary Percutaneous Coronary Intervention

BACKGROUND

Sleep-disordered breathing (SDB) has been recognized as an important risk factor for cardiovascular diseases; however, the impact of SDB on long-term outcomes in patients with acute coronary syndrome has not been fully evaluated.

METHODS AND RESULTS

We performed overnight cardiorespiratory monitoring of 241 patients with acute coronary syndrome who were successfully treated with primary percutaneous coronary intervention between January 2005 and December 2008. The presence of SDB was defined as apnea-hypopnea index ≥5 events per hour. The end point was incidence of major adverse cardiocerebrovascular events, defined as a composite of all-cause death, recurrence of acute coronary syndrome, nonfatal stroke, and hospital admission for congestive heart failure. Patients were followed for a median period of 5.6 years. Among the 241 patients who were finally enrolled, comorbidity of SDB with acute coronary syndrome was found in 126 patients (52.3%). The cumulative incidence of major adverse cardiocerebrovascular events was significantly higher in patients with SDB than in those without SDB (21.4% versus 7.8%, P=0.006). Multivariable analysis revealed that the presence of SDB was a significant predictor of major adverse cardiocerebrovascular events (hazard ratio 2.28, 95% CI 1.06-4.92; P=0.035).

CONCLUSIONS

The study's results showed that the presence of SDB among patients with acute coronary syndrome following primary percutaneous coronary intervention is associated with a higher incidence of major adverse cardiocerebrovascular events during long-term follow-up.